1. Field of the Invention
The present invention relates to an operating knob, and particularly to a high precision operating knob having a screw therein/thereon, the knob being suitable for a user to rotate.
2. Description of the Related Art
In the prior art, an operating knob used to adjust the setting of test and measuring equipment or machines is usually a simple knob mounted on a rod. This type of operating knob is often hexagonal in shape. Such a knob defines six recesses in side edges thereof, each recess corresponding to a side of a hexagon, for permitting the fingers, including the thumb, of a user to rotate the knob. When using this type of knob to make fine accuracy adjustments, the thumb must be parallel to the other four fingers. This orientation of the thumb and finger is tiring and makes precise movement of the knob difficult.
Hence, an improved operating knob is required to overcome the disadvantages of the prior art.
A main object of the present invention is to provide a high-precision operating knob suitable for a user to handle when adjusting a machine setting with precision.
An operating knob comprises an upper knob portion, a lower knob portion, and a neck portion connecting the upper knob portion with the lower knob portion. The upper knob portion is hexagonal in shape and defines six first recesses in side edges thereof. The lower knob portion defines a plurality of second recesses in a side edge thereof. A screw hole is defined axially through the operating knob, penetrating through the lower knob portion and into the upper knob portion. The knob is mounted in a position on a place of equipment or a machine such that the axis of the screw hole is substantially perpendicular to the user""s forearm. To use the high-precision operating knob, two to four of the user""s fingers are engaged with the first recesses of the upper knob portion, and the thumb is pressed against the side edge of the lower knob portion. When turning the knob, the two to four fingers of the user rotate the upper knob portion in a clockwise or anti-clockwise direction and the thumb pushes the side edge of the lower knob portion in the clockwise or anti-clockwise direction. During this rotation movement, the user""s fingers are substantially perpendicular to the user""s thumb.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.